That thing is moving
The Scream Extractor is a scream-extracting machine built and maintained by Randall Boggs and Fungus in Monsters, Inc. It is intended to collect scream from children much more efficiently than traditional scaring techniques, which have become increasingly ineffective for the monsters.

Randall and Fungus intend to use the machine on Boo. When they discover they've accidentally kidnapped Mike, they put him into it instead. Sulley rescues him, and puts Fungus into the machine. Undeterred, Randall, Fungus, and Mr. Waternoose attempt to use the machine on Boo while Mike and Sulley are exiled in the human world, but Sulley returns just in time to save Boo and foil their plans again, while destroying the machine in the process.